Certain ethnic groups tend to follow certain naming patterns when choosing names for children. Keep in mind that these patterns are cultural norms. They are not set in statute. They are not part of an ecclesiastical edict. There can be exceptions, particularly when both grandfathers (or grandmothers) have the same first name or when there has been a significant argument with a certain relative.
Use the naming patterns as a suggestive clues not as an established certainty.
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